3 * $Id: twofish-mktab.c,v 1.4 2000/10/08 12:08:10 mdw Exp $
5 * Build constant tables for Twofish
7 * (c) 2000 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Catacomb.
14 * Catacomb is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
19 * Catacomb is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
24 * You should have received a copy of the GNU Library General Public
25 * License along with Catacomb; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
30 /*----- Revision history --------------------------------------------------*
32 * $Log: twofish-mktab.c,v $
33 * Revision 1.4 2000/10/08 12:08:10 mdw
34 * Escape literal newlines in output string.
36 * Revision 1.3 2000/06/26 17:14:42 mdw
37 * (rslog): Ensure that log(1) = 0 (not 255, as previously). While the two
38 * are strictly equivalent, it means that the exp table is larger than it
39 * otherwise needs to be.
41 * Revision 1.2 2000/06/18 23:12:15 mdw
42 * Change typesetting of Galois Field names.
44 * Revision 1.1 2000/06/17 12:10:17 mdw
49 /*----- Header files ------------------------------------------------------*/
54 #include <mLib/bits.h>
56 /*----- Data structures ---------------------------------------------------*/
58 typedef struct { octet t
[4][16]; } t_tab
;
59 typedef struct { octet q
[256]; } q_tab
;
61 /*----- Various Twofish tables --------------------------------------------*/
63 /* --- The t-tables --- */
65 static const t_tab qt0
= {{
66 { 0x8, 0x1, 0x7, 0xd, 0x6, 0xf, 0x3, 0x2,
67 0x0, 0xb, 0x5, 0x9, 0xe, 0xc, 0xa, 0x4 },
68 { 0xe, 0xc, 0xb, 0x8, 0x1, 0x2, 0x3, 0x5,
69 0xf, 0x4, 0xa, 0x6, 0x7, 0x0, 0x9, 0xd },
70 { 0xb, 0xa, 0x5, 0xe, 0x6, 0xd, 0x9, 0x0,
71 0xc, 0x8, 0xf, 0x3, 0x2, 0x4, 0x7, 0x1 },
72 { 0xd, 0x7, 0xf, 0x4, 0x1, 0x2, 0x6, 0xe,
73 0x9, 0xb, 0x3, 0x0, 0x8, 0x5, 0xc, 0xa }
76 static const t_tab qt1
= {{
77 { 0x2, 0x8, 0xb, 0xd, 0xf, 0x7, 0x6, 0xe,
78 0x3, 0x1, 0x9, 0x4, 0x0, 0xa, 0xc, 0x5 },
79 { 0x1, 0xe, 0x2, 0xb, 0x4, 0xc, 0x3, 0x7,
80 0x6, 0xd, 0xa, 0x5, 0xf, 0x9, 0x0, 0x8 },
81 { 0x4, 0xc, 0x7, 0x5, 0x1, 0x6, 0x9, 0xa,
82 0x0, 0xe, 0xd, 0x8, 0x2, 0xb, 0x3, 0xf },
83 { 0xb, 0x9, 0x5, 0x1, 0xc, 0x3, 0xd, 0xe,
84 0x6, 0x4, 0x7, 0xf, 0x2, 0x0, 0x8, 0xa }
89 /* --- The MDS and Reed-Solomon matrices --- */
91 static const octet mds
[16] = {
92 0x01, 0xef, 0x5b, 0x5b,
93 0x5b, 0xef, 0xef, 0x01,
94 0xef, 0x5b, 0x01, 0xef,
95 0xef, 0x01, 0xef, 0x5b
98 static const octet rs
[32] = {
99 0x01, 0xa4, 0x55, 0x87, 0x5a, 0x58, 0xdb, 0x9e,
100 0xa4, 0x56, 0x82, 0xf3, 0x1e, 0xc6, 0x68, 0xe5,
101 0x02, 0xa1, 0xfc, 0xc1, 0x47, 0xae, 0x3d, 0x19,
102 0xa4, 0x55, 0x87, 0x5a, 0x58, 0xdb, 0x9e, 0x03
105 /*----- Magic macros ------------------------------------------------------*/
107 #define ROR4(x) ((((x) >> 1) | ((x) << 3)) & 15)
109 /*----- Building and printing @q@ tables ----------------------------------*/
113 * Arguments: @q_tab *q@ = pointer to output @q@ table
114 * @const t_tab *t@ = pointer to input @t@ table
115 * @const char *name@ = name of @q@ table
119 * Use: Constructs a 256-entry @q@-table.
122 static void mkq(q_tab
*q
, const t_tab
*t
, const char *name
)
127 /* --- Ensure the t-table is well-formed --- */
129 for (i
= 0; i
< 4; i
++) {
133 for (j
= 0; j
< 16; j
++) {
135 fprintf(stderr
, "duplicate %i in %s[%i] (col %i and %i)\n",
136 t
->t
[i
][j
], name
, i
, j
, f
[t
->t
[i
][j
]]);
146 /* --- Construct the @q@ table --- */
148 for (i
= 0; i
< 256; i
++) {
149 int a
= i
>> 4, b
= i
& 15;
150 int aa
= t
->t
[0][a
^ b
], bb
= t
->t
[1][a
^ ((a
<< 3) & 15) ^ ROR4(b
)];
151 a
= t
->t
[2][aa
^ bb
], b
= t
->t
[3][aa
^ ((aa
<< 3) & 15) ^ ROR4(bb
)];
152 q
->q
[i
] = a
| (b
<< 4);
155 /* Consider testing @q@ for linear and differential properties here */
158 /* --- @printq@ --- *
160 * Arguments: @const q_tab *t@ = pointer to table
161 * @const char *name@ = pointer to table name
165 * Use: Prints a q table.
168 static void printq(const q_tab
*q
, const char *name
)
174 #define TWOFISH_%s { \\\n\
177 for (i
= 0; i
< 256; i
++) {
178 printf("0x%02x", q
->q
[i
]);
181 fputs(" \\\n}\n\n", stdout
);
183 fputs(", \\\n ", stdout
);
189 /*----- %$\gf{2^8}$% arithmetic -------------------------------------------*/
191 #define MDS_MOD 0x169
196 * Arguments: @unsigned x, y@ = polynomials over %$\gf{2^8}$%
197 * @unsigned m@ = modulus
199 * Returns: The product of two polynomials.
201 * Use: Computes a product of polynomials, quite slowly.
204 static unsigned mul(unsigned x
, unsigned y
, unsigned m
)
209 for (i
= 0; i
< 8; i
++) {
223 * Arguments: @octet *d@ = destination vector
224 * @const octet *p@ = matrix of bytes
225 * @const octet *q@ = vector from somewhere else
226 * @size_t r@ = size of destination or number of rows in matrix
227 * @size_t n@ = length of row and vector
228 * @unsigned m@ = modulus polynomial
232 * Use: Computes an inner product of matrices over the finite field
233 * %$\gf{2^8}[x]/(m(x))$%. This isn't particularly rapid.
236 static void mmul(octet
*d
, const octet
*p
, const octet
*q
,
237 size_t r
, size_t n
, unsigned m
)
244 for (i
= 0; i
< n
; i
++)
245 a
^= mul(*p
++, *qq
++, m
);
257 * Use: Prints the MDS/q table.
260 static void qmds(void)
264 static const q_tab
*q
[4] = { &q1
, &q0
, &q1
, &q0
};
266 for (i
= 0; i
< 4; i
++) {
267 octet in
[4] = { 0, 0, 0, 0 };
270 for (j
= 0; j
< 256; j
++) {
272 mmul(out
, mds
, in
, 4, 4, MDS_MOD
);
273 t
[i
][j
] = LOAD32_L(out
);
278 /* --- Expanded MDS tables --- *\n\
280 * The table contains output vectors for computing the result of pushing\n\
281 * bytes through appropriate @q@ tables and the MDS matrix.\n\
284 #define TWOFISH_QMDS { \\");
285 for (i
= 0; i
< 4; i
++) {
286 fputs(" { ", stdout
);
287 for (j
= 0; j
< 256; j
++) {
288 printf("0x%08lx", (unsigned long)t
[i
][j
]);
295 } else if (j
% 4 == 3)
296 fputs(", \\\n ", stdout
);
311 * Use: Produces the log and antilog tables for doing the RS
312 * arithmetic efficiently.
315 static void rslog(void)
324 for (i
= 0; i
< 255; i
++) {
333 for (i
= 0; i
< 32; i
++) {
334 if (rslog
[rs
[i
]] > x
)
339 /* --- Reed-Solomon log tables --- *\n\
341 * The Reed-Solomon multiplies are accelerated by using log tables.\n\
344 #define TWOFISH_RSLOG { \\\n\
347 for (i
= 0; i
< 256; i
++) {
348 printf("0x%02x", rslog
[i
]);
352 fputs(", \\\n ", stdout
);
358 #define TWOFISH_RSEXP { \\\n\
361 for (i
= 0; i
< 255 + x
+ 1; i
++) {
362 printf("0x%02x", rsexp
[i
% 255]);
366 fputs(", \\\n ", stdout
);
372 /* --- Reed-Solomon matrix with log entries --- */\n\
374 #define TWOFISH_RS { \\\n\
377 for (i
= 0; i
< 32; i
++) {
378 printf("0x%02x", rslog
[rs
[i
]]);
382 fputs(", \\\n ", stdout
);
388 /*----- Main program ------------------------------------------------------*/
397 * Twofish q tables [generated]\n\
400 #ifndef CATACOMB_TWOFISH_TAB_H\n\
401 #define CATACOMB_TWOFISH_TAB_H\n\
405 /* --- The q tables --- */
408 /* --- Precomputed @q@ tables --- */\n\
410 mkq(&q0
, &qt0
, "qt0");
411 mkq(&q1
, &qt1
, "qt1");
415 /* --- The MDS/q tables --- */
424 if (fclose(stdout
)) {
425 fprintf(stderr
, "error writing data\n");
432 /*----- That's all, folks -------------------------------------------------*/